Engineering of <i>Pterocarpus indicus</i> -loaded silver nanoparticles for anti-arthritis assessment: a targeted delivery approach

Green-synthesized silver nanoparticles were developed using Pterocarpus indicus bark extract and evaluated for their anti-arthritic potential. The synthesized nanoparticles were characterized by ultraviolet-visible spectroscopy, dynamic light scattering, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. Pterocarpus indicus-loaded silver nanoparticles exhibited an average particle size of 99.34 nm, a Polydispersity Index of 0.3522, and a zeta potential of −23.15 mV, indicating good stability. Morphological studies confirmed spherical, crystalline nanoparticles ranging from 20 to 50 nm. Cytocompatibility analysis on L929 fibroblast cells demonstrated low toxicity with 88.53% cell viability at 100 µg/ml. The nanoparticles showed notable antioxidant activity and effectively inhibited protein denaturation in vitro. In vivo anti-inflammatory studies revealed significant inhibition of carrageenan-induced paw edema, while treatment of complete Freund’s adjuvant-induced arthritic rats markedly reduced paw swelling and improved histopathological alterations compared with the disease control group. These findings suggest that green-synthesized PI-AgNPs possess promising anti-inflammatory and anti-arthritic properties with potential biomedical applications.